Method and system for sidelobe reduction using antipodal signaling

Abstract

Embodiments of the present invention provide a system and method for reducing the power of a UWB signal over a desired range of frequencies. Embodiments of the present invention reduce power over the desired range of frequencies by reducing the sidelobe power of tones comprising the UWB signal. Embodiments of the present invention reduce sidelobe power by inverse signaling one or more tones comprising the UWB signal.

1. A method of reducing sidelobes in a Ultra-Wideband (UWB) signal, comprising:
 generating a plurality of tones by the transmitter; 
 mapping one or more of the plurality of tones such that an inverted tone is adjacent to a non-inverted tone using a first matrix; and 
 forming a Ultra-Wideband (UWB) signal using the plurality of tones. 
 
     
     
       2. The method of  claim 1 , wherein the entries in the first matrix have a magnitude less than or equal to 1. 
     
     
       3. The method of  claim 2 , wherein the magnitude is approximately an inverse power of two. 
     
     
       4. The method of  claim 1 , wherein the first matrix is a two by two matrix. 
     
     
       5. The method of  claim 4 , wherein every entry in the first matrix not on a main diagonal of the first matrix is negative. 
     
     
       6. The method of  claim 1 , wherein the first matrix is an invertible matrix. 
     
     
       7. The method of  claim 1 , further comprising receiving the UWB signal and demapping the inverted tone, wherein demapping the inverted tone comprises mapping tones using a second matrix, wherein the second matrix is substantially the inverse of the first matrix. 
     
     
       8. The method of  claim 1 , further comprising receiving the UWB signal and demapping the inverted tone. 
     
     
       9. The method of  claim 8 , wherein demapping the inverted tone comprises using a decoder. 
     
     
       10. A system capable of shaping the power spectrum of a UWB signal, comprising:
 a transmitter configured to:
 generate a plurality of tones; 
 
 map one or more of the plurality of tones such that an inverted tone is adjacent to a non-inverted tone using a first matrix; and 
 form a UWB signal using the plurality of tones. 
 
     
     
       11. The system of  claim 10 , wherein the entries in the first matrix have a magnitude less than or equal to 1. 
     
     
       12. The system of  claim 11 , wherein the magnitude is approximately an inverse power of two. 
     
     
       13. The system of  claim 10 , wherein the first matrix is a two by two matrix. 
     
     
       14. The system of  claim 13 , wherein every entry in the first matrix not on a main diagonal of the first matrix is negative. 
     
     
       15. The system of  claim 10 , wherein the first matrix is an invertible matrix. 
     
     
       16. The system of  claim 10 , further comprising:
 a receiver configured to: 
 receive the UWB signal; and 
 demap the inverted tone using a second matrix, wherein the second matrix is substantially the inverse of the first matrix. 
 
     
     
       17. The system of  claim 1 , further comprising:
 a receiver configured to: 
 receive the UWB signal; and 
 demap the inverted tone. 
 
     
     
       18. The system of  claim 17 , wherein the receiver is further configured to demap the inverted tone using a decoder. 
     
     
       19. A non-transitory computer readable medium comprising a set of computer instructions, said set of computer instructions executable to:
 generate a plurality of tones; 
 map one or more of the plurality of tones such that an inverted tone is adjacent to a non-inverted tone using a matrix; and 
 form a UWB signal using the plurality of tones. 
 
     
     
       20. The non-transitory computer readable medium of  claim 19 , wherein the entries in the matrix have a magnitude less than or equal to 1. 
     
     
       21. The non-transitory computer readable medium of  claim 20 , wherein the magnitude is approximately an inverse power of two. 
     
     
       22. The non-transitory computer readable medium of  claim 19 , wherein the matrix is a two by two matrix. 
     
     
       23. The non-transitory computer readable medium of  claim 22 , wherein every entry in the matrix not on a main diagonal of the matrix is negative. 
     
     
       24. The non-transitory computer readable medium of  claim 19 , wherein the matrix is an invertible matrix.